Maternal Inhalation of Nanomaterials can Influence Fetal Health

NIEHS grantees report evidence that maternal inhalation of engineered nanomaterials can have fetal and maternal microvascular effects in an animal model. Microcirculation is important for fetal health because it regulates blood flow distribution and protects downstream tissues from high arterial pressures and blood flow rates.

The researchers designed a study to evaluate the microvascular effects of maternal exposure to nanomaterials and to find out if the Barker hypothesis applies at the microvascular level. The Barker hypothesis proposes that fetal development within a hostile gestational environment may predispose or program future sensitivity. The researchers placed pregnant rats in an inhalation chamber, where they were exposed to nanotitanium dioxide aerosols for five hours per day for an average of 8.2 days.

Exposure to the engineered nanomaterials led to significant maternal and fetal microvascular dysfunction. Fetal microvessels isolated from exposed dams demonstrated significant impairments to signals of vasodilation specific to mechanistic signaling and shear stress. The maternal uterine microvascular reactivity was also affected. The researchers conclude that maternal inhalation of engineered nanomaterials can influence fetal health and that the Barker hypothesis does apply at the microvascular level.